The root has an outer layer of cells called the epidermis, which surrounds areas of ground tissue and vascular tissue. The cells of the outer root sheath normally display a number of keratins, adhesion molecules, cytokines and growth factor receptors that are different from those expressed by epidermal cells. A hair follicle is a stocking-like structure that contains cells and connective tissue and surrounds the root of a hair. This structure explains why we do not feel any pain whilst our hair is being cut. The papilla contains an artery that nourishes the root of the hair. …cells of the epidermis produce root hairs near the root apex. Secondary cortex or phelloderm is parenchymatous and the cells contain chlorophyll in young stages. Figure 5.1.1 – Layers of Skin: The skin is composed of two main layers: the epidermis, made of closely packed epithelial cells, and the dermis, made of dense, irregular connective tissue that houses blood vessels, hair follicles, sweat glands, and other structures. The hair shaft is made up of dead cells that have turned into keratin and binding material, together with small amounts of water. The hair shaft is formed of three layers: The medulla – the deepest layer of the hair shaft, only seen in large and thick hairs. Since its cell walls are heavily suberized and impermeable to water its apparent function is to keep the water and nutrients (which are absorbed in the root zone further down the root) from leaking out through the cortex. Endodermis is well-developed, single-layered and present in the young root but it gets crushed due to the secondary growth in later stages. Pericycles: 7. It exists within the dermis and the epidermis, the two top layers of the skin.For a helpful visual, think of the hair follicle as a vase and the hair as the stem of a flower. The epidermis and its waxy cuticle provide a protective barrier against mechanical injury, water loss, and infection. The root hairs have fundamental importance in absorption of water and nutrients and in attachment of… Read More; trees ... superficial covering of a hair consisting of a single layer of cells that overlap one another. Root hair are absent. Each hair has three layers: the medulla (pronounced: meh-DULL-uh) at the center, which is soft The cells are rounded with many intercellular spaces in between. Lateral Root. C) hair root. region of a hair that projects above skin surface. 6. Epidermis, in botany, outermost, protoderm-derived layer of cells covering the stem, root, leaf, flower, fruit, and seed parts of a plant. As cells multiply and make keratin to harden the structure, they're pushed up the follicle and through the skin's surface as a shaft of hair. 4. These cells are generally thin-walled, in contrast to the cells of the cortex, lying below the surface, which ultimately may become very thick-walled. Lateral roots are produced when cells in the pericycle, the layer of cells surrounding the central vascular cylinder, begin to divide, form additional cell layers that push through the outer cell layers of the primary root, and ultimately organize a second root meristem. All three zones are in the first centimeter or so of the root tip. Beginning at the first root hair is the zone of cell maturation where the root cells begin to differentiate into special cell types. Various modified epidermal cells regulate The cells in all of the layers except the stratum basale are called keratinocytes. several cell layers thick, with intermediate filaments, keratinocytes and Langerhans cells. 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